This paper models the behavior of the Brazilian professional football's fans concerning their presence in the stadiums. So, it aims to test the fidelity of them in the 2004 National League. In this direction, it estimates, regarding the twelve biggest teams, for which fans the expectation about the games's result is able to explain their presence in the stadiums. Hence, it follows two steps, both about the 2004 National Championship: first, it estimates, game by game, a vector with the win, loss and tie probabilities, using a Ordered Logit; second, it tries to capture for which teams fans this vector are able to explain their presence in the stadiums. For the championship said above, only three teams have non-loyalty fans: Atlético Mineiro, Grêmio and Internacional de Porto Alegre.
